Such involved artwork, as that created for the Book of Kells, required a sturdy material to absorb the pigments and sustain the elements of time. Calfskin vellum was used for this purpose. To create the 680 pages of the book, 340 calfskins were cleaned and left to soak in a limewater mixture for several weeks. The skins were then removed from the liquid and scraped to remove any remnants of hair and debris. The skin was then stretched to a fine surface that was then treated and prepared for accepting ink. Most of these inks were made from the juices of the local flora and fauna, the very dark colors being created from oak galls – a growth forming on the bark of oak trees as a result of fungus and insects. The vivid colors of the pigments used in the illustrations were created using several different materials and techniques. There are five central colors used in combination with the dark brown and black inks.

1. Red – Red lead was used to produce this bright orange-tinged color.  This pigment lay on the surface of the vellum and has flaked off in some areas over the years leaving a white vacant space.
2. Green – Copper was used to produce the emerald shade of green.  This pigment was absorbed deeply into the vellum seeping through to the other side in some cases.  This is due to the acidity of the metal.
3. Yellow – Pale colored soil mixed with egg whites was used to produce this golden hue.  The luminous properties of the egg white are what give it its surface sheen, which effectively mimics gold foil.
4. Purple – Indigo, obtained through trade with northern Europe, was used to produce the rich violet tones.
5. Blue – Lapis lazuli was imported from Asia to produce the sapphire pigment.

These last two colors, purple and blue, illustrate the flourishing trade industry, which was quickly reducing Ireland’s isolation from the continent. As is customary with any trading system, knowledge and influence is exchanged along with goods and natural resources.​¹

¹ George Otto Simms, Exploring The Book of Kells, The O’Brien Press Ltd., Dublin, Ireland, 1988 pages 26-32.